The present invention relates to a sense amplifier circuit and a semiconductor memory device. For example, the present invention can be suitably used for a sense amplifier circuit and a semiconductor memory device that include a sensing transistor.
In recent years, the applications of microcomputer products that are semiconductor devices including memories such as flash memories have expanded to low-cost electronic apparatuses in addition to high-performance electronic apparatuses. The size of chips has been decreasing in the market of low-cost electronic apparatuses where cost is the primary concern.
As the size of each chip of the semiconductor device decreases, a power supply and a ground capacity inside the chip relatively decreases as well. This causes degradation of noise immunity for noise that is generated in the power supply and a ground potential. In particular, since the standardization of Electro Magnetic Susceptibility (EMS) has been promoted, it is required to improve noise immunity.
As an example of such a semiconductor device, Japanese Unexamined Patent Application Publication No. 2009-181599 discloses a semiconductor memory device that includes a related sense amplifier circuit.